VxGather just collects a group of configuration and other log files depnding on any enabled logging, as such it is just a CAB file containing lots of other files.

Exactly what to look for when reading the other files kind of depends on what the fault your are investigating and would take too long to explain in any depth as an answer on a forum.

Typically we are interested in error messages close to the time of the failure - which is why we try and insist that logs are gathered after the failure and the job log that shows a visible error is included to give us the timestamp.

One thing to watch out for in the debug logs which can be confusing is that the way Backup Exec confirms if certain resources are available is to try and access them, if a failure occurs this is reported as an error in the (typically beremote) log , however it might be an expected error (i.e. asking if Exchange is available and getting an error is expected if the server is a SQL server, but not expected if it is an Exchange server) This of course means when reading logs (particularly near service or job start) you have to be aware of what is actually configured on the server as not every error message in a log is really an error.